A variety of technical means can be used on ATMs and other self-service equipment to detect the presence of foreign objects (such as side-recording devices, code stealers, etc.) around the self-service equipment card reader. Advantages and disadvantages of the different means are briefly described as follows:
1, light judgment:
The use of infrared light reflection principle, located in the ATM machine around the card reader through some light transmission holes, from the self-service equipment through the light transmission holes from the inside to the outside of the infrared light, when the suspects in the card reader to add other devices, generally block part of the light transmission holes, at this time it can be determined that there is an illegal addition of equipment.
The disadvantage of this method is that it must be punched in the ATM machine, destroying the original structure of the ATM machine. In addition, if there are foreign objects (dust, etc.) blocking the light-through hole or environmental light changes and other factors will be false alarms, false alarm rate is very high; if the stolen card side recording device in the installation of bypassing the light-through hole will be missed.
Therefore, the feasibility of this program is not high in practical use.
2, electromagnetic field judgment:
The use of magnetic field strength sensors or electromagnetic field strength sensing equipment to detect the ATM card reader around the electric and magnetic field changes compared with the normal situation, such as electric and magnetic field anomalies are judged to be the existence of a card thief.
This method belongs to the proximity detection technology, but also must be in the ATM machine to play the installation of holes, change the original structure of the ATM machine, if the ATM machine is a metal shell, the detection equipment must be external, which in itself becomes a security risk; in addition, from the principle of as long as there is a change in the magnetic field strength of the objects around the presence of false alarms, and if you adjust down the detection of the sensitivity of the leakage of alarms, and sensitivity adjustments It is difficult to grasp the scale of sensitivity adjustment.
3, the use of image processing technology to analyze the image of the ATM card reader to find out the characteristics of the original card reader image comparison, if there is anomaly, it is determined that there is a code stealer.
This method is sensitive to the illumination of the environment, the image clarity requirements are very high, once you can not meet will bring a very high rate of false alarms; of course, its biggest drawback lies in the absence of anti-counterfeiting features, if the installation of the appearance of the pirate card reader and the color and the original reader is similar to that from the video image can not be distinguished, which leads to serious underreporting.
Surveillance cameras have the inherent characteristics of a flat image, so it is difficult to use flat image analysis to solve the problem of identifying disguised side recording devices. The results of practical use are also very unsatisfactory.
Analysis of the characteristics and advantages of the anti-side-recording system based on the principle of laser ranging
The crime of card skimming that occurs at ATMs is characterized by one and the same feature: the addition of side-recording devices (code skimmers, fake keyboards, etc.). Any retrofitting means that the physical thickness of certain important parts of the ATM (card insertion port, keyboard, etc.) has undergone abnormal changes, through high-precision laser measurement sensors real-time monitoring of these sensitive parts of the spatial height of the situation changes in real time to determine whether the normal card insertion port has been retrofitted with a side-recording device, etc., so as to be able to send out a warning in the process of retrofitting
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